The present invention relates to a brake apparatus for use in braking of a vehicle.
As a hydraulic brake apparatus for use in braking a vehicle such as an automobile, for example, there is known a brake apparatus disclosed in Japanese Patent Application Public Disclosure No. 2008-239142. This brake apparatus controls an operation of an electric motor based on relative positions of an input piston, which is coupled with a brake pedal for issuing a brake instruction, and an assist piston, which is configured to be driven by the electric motor, to generate a brake hydraulic pressure in a master cylinder, thereby controlling a brake force. According to this brake apparatus, it is possible to perform various kinds of brake control such as boosting control, brake assist control, and regenerative cooperative control.
This kind of brake apparatus requires accurate setting of a control position, which is a holding position of the assist piston configured to be driven by the electric motor when the brake is released, in order to realize excellent responsiveness of vehicle braking in response to a brake instruction.